The present invention relates to an apparatus and method for controlling a car, and particularly relates to a car control apparatus and method for controlling operation variables of a regulator which regulates the operating condition of a car.
As a typical one of car control apparatus there is known an internal combustion engine control apparatus.
In the internal combustion engine control apparatus, the operation condition of the internal combustion engine is detected, the fuel flow necessary at present is calculated by means of an arithemtic unit, and the injection valve is driven on the basis of the result of the calculation.
In such an internal combustion engine control apparatus, however, there has been a problem in that the secular change in injection valve and/or air flow sensor or variations in manufacturing the same makes it difficult to obtain a proper fuel flow.
To solve such a problem, there has been proposed an apparatus additionally provided with a calibration learning function, for example, as disclosed in U.S. Pat. No. 4,130,095.
According to the calibration learning function, when a correction signal based on an output signal of an oxygen sensor provided in an exhaust system deviates from an ideal state, the amount of deviation is regarded as an amount of the secular change or variations in production and stored in a rewritable memory element. In practice, the above amount of deviation is used as a correction term in a computing equation for determining a fuel flow.
In an internal combustion engine control apparatus, ignition timing control is carried out in addition to the above-mentioned fuel control.
One of basic parameters for determining the ignition timing is the amount of air sucked into an internal combustion engine every cycle.
In such a control apparatus, there are the following problems. One of the problems is that when the output of an air flow amount varies due to secular change or variations in production as described above, it becomes impossible to obtain the ignition timing accurately because the variations in the air flow sensor per se for detecting the amount of air which is one of a basic parameters for determining the ignition timing cannot be detected, while the fuel feed amount can ultimately be corrected by means of the calibration learning function.
A second one of the problems is as follows. In such a control apparatus, control constants for determining the fuel amount etc., are stored in a memory element or electronic memory means so that those control constants are read out from the memory element or electronic memory means to determine the fuel amount in operating the internal combustion engine. In such a control apparatus, however, the control constants to be stored in the memory element or electronic memory means are determined in a manner such that under the condition that the internal combustion engine is being actually operated, values of control constants required for the operation of the engine, for example, the values with which the exhaust harmful components becomes minimum, the values with which the output torque becomes maximum, and the like, are looked-up in various operational regions of the engine to thereby obtain the most optimum values which satisfy the required characteristics while changing the values of control constants again and again artificially. Accordingly, it takes a long time and many hands to finally determine the values of control constants and there is a limit in accuracy of the thus obtained control constants.